Question: $\dfrac{9}{8} - \dfrac{2}{12} = {?}$
$ = {\dfrac{9 \times 3}{8 \times 3}} - {\dfrac{2 \times 2}{12 \times 2}} $ $ = {\dfrac{27}{24}} - {\dfrac{4}{24}} $ $ = \dfrac{{27} - {4}}{24} $ $ = \dfrac{23}{24}$